The present invention relates generally to mechanism for measuring the temperature of a hot chuck surface.
Semiconductor reliability tests, which are known as wafer level reliability (WLR) tests, are typically carried out at ambient temperatures as high as 350° C. The duration of such WLR tests can range from several minutes to several weeks. When a WLR test is performed on many dice across a wafer, either sequentially or simultaneously, it is important to maintain the entire wafer at a uniform temperature.
In order to achieve and maintain a uniform temperature across the entire wafer, the temperature of the wafer needs to be measured. A cost-efficient, reliable wafer temperature measurement tool is therefore desirable.